If you ________ be quiet, I will tell you what happened.
You can go out, _________ you promise to be back before 11 o'clock.
Unless _________ by the police, you should keep silent over the accident.
The media today can draw public attention to situation ________ help is actually needed.
_________ in the mountain for more than 2 days, the climbers looked pale and weak.
Since the film “Life of Pi” was on, it _________ more and more people around the world.